Download APKs from: https://github.com/medic/cht-gateway/releases
An SMS gateway for Android. Send and receive SMS from your webapp via an Android phone.
+--------+ +-----------+
| web | | cht- | <-------- SMS
| server | <---- HTTP ---- | gateway |
| | | (android) | --------> SMS
+--------+ +-----------+
Install the latest APK from https://github.com/medic/cht-gateway/releases
If you're configuring cht-gateway for use with hosted CHT-Core, with a URL of e.g. https://myproject.dev.medicmobile.org and a username of gateway and a password of topSecret, fill in the settings as follows:
Please note that in the medic-branded build, the username is hard-coded as gateway, and cannot be changed.
Instance name: myproject [dev]
Password: topSecret
WebappUrl: https://gateway:[email protected]/api/sms
If you're configuring cht-gateway for use with other services, you will need to use the generic build of cht-gateway, and find out the value for CHT URL from your tech support.
Some CDMA networks have limited support for multipart SMS messages. This can occur within the same network, or only when sending SMS from a GSM network to a CDMA network. Check this box if cht-gateway is running on a GSM network and:
- multipart messages sent to CDMA phones never arrive; or
- multipart messages sent to CDMA phones are truncated
When using HTTP Basic Auth with gateway, all characters in the password must be chosen from the ISO-8859-1 characterset, excluding #, /, ?, @.
This is the API specification for communications between cht-gateway and a web server. Messages in both directions are application/json.
Where a list of values is expected but there are no values provided, it is acceptable to:
- provide a
nullvalue; or - provide an empty array (
[]); or - omit the field completely
Bar array behaviour specified above, cht-gateway must include fields specified in this document, and the web server must include all expected fields in its responses. Either party may include extra fields as they see fit.
N.B. messages are considered duplicate by cht-gateway if they have identical values for id. The webapp is expected to do the same.
cht-gateway will not re-process duplicate webapp-originating messages.
cht-gateway may forward a webapp-terminating message to the webapp multiple times.
cht-gateway may forward a delivery status report to the webapp multiple times for the same message. This should indicate a change of state, but duplicate delivery reports may be delivered in some circumstances, including:
- the phone receives multiple delivery status reports from the mobile network for the same message
cht-gatewayfailed to process the webapp's response when the delivery report was last forwarded fromcht-gatewayto webapp
cht-gateway supports HTTP Basic Auth. Just include the username and password for your web endpoint when configuring cht-gateway, e.g.:
https://username:[email protected]/cht-gateway-api-endpoint
The entire API should be implemented by a webapp at a single endpoint, e.g. https://exmaple.com/cht-gateway-api-endpoint
Expected response:
{
"medic-gateway": true
}
cht-gateway will accept and process any relevant data received in a response. However, it may choose to only send certain types of information in a particular request (e.g. only provide a webapp-terminating SMS), and will also poll the web service periodically for webapp-originating messages, even if it has no new data to pass to the web service.
The following headers will be set by requests:
| header | value |
|---|---|
Accept |
application/json |
Accept-Charset |
utf-8 |
Accept-Encoding |
gzip |
Cache-Control |
no-cache |
Content-Type |
application/json |
Requests and responses may be sent with Content-Encoding set to gzip.
{
"messages": [
{
"id": <String: uuid, generated by `cht-gateway`>,
"from": <String: international phone number>,
"content": <String: message content>,
"sms_sent": <long: ms since unix epoch that message was sent>,
"sms_received": <long: ms since unix epoch that message was received>
},
...
],
"updates": [
{
"id": <String: uuid, generated by webapp>,
"status": <String: PENDING|SENT|DELIVERED|FAILED>,
"reason": <String: failure reason (optional - only present for status:FAILED)>
},
...
],
}
The status field is defined as follows.
| Status | Description |
|---|---|
| PENDING | The message has been sent to the gateway's network |
| SENT | The message has been sent to the recipient's network |
| DELIVERED | The message has been received by the recipient's phone |
| FAILED | The delivery has failed and will not be retried |
Clients may respond with any status code in the 200-299 range, as they feel is
appropriate. cht-gateway will treat all of these statuses the same.
{
"messages": [
{
"id": <String: uuid, generated by webapp>,
"to": <String: local or international phone number>,
"content": <String: message content>
},
...
],
}
Response codes of 400 and above will be treated as errors.
If the response's Content-Type header is set to application/json, cht-gateway will attempt to parse the body as JSON. The following structure is expected:
{
"error": true,
"message": <String: error message>
}
The message property may be logged and/or displayed to users in the cht-gateway UI.
Treatment of response codes below 200 and between 300 and 399 will probably be handled sensibly by Android.
Gateway will retry to send the SMS when any of these errors occurs: RESULT_ERROR_NO_SERVICE, RESULT_ERROR_NULL_PDU and RESULT_ERROR_RADIO_OFF.
-
A possible temporary error occurs and Gateway retries sending the SMS: 1.1 SMS status will be updated to
UNSENT, so Gateway will find it and add it into thesend queueautomatically. 1.2 SMS'retry counterincreases by 1. 1.3 The retry attempt is scheduled based on this formula:SMS' last activity time + ( 1 minute * (retry counter ^ 1.5) ). This means the time between retries is incremental. 1.4 Gateway logs: the error, the retry counter and the retry scheduled time. Sample:Sending SMS to +1123123123 failed (cause: radio off) Retry #5 in 15 min -
Gateway has a maximum limit of attempts to retry sending SMS (currently 20), If this is reached then: 2.1 Gateway will hard fail the SMS by updating its status to
FAILEDand won't retry again. 2.2 Gateway logs error. Sample:Sending message to +1123123123 failed (cause: radio off) Not retrying -
At this point the user has the option of manually select the SMS and press
Retrybutton. 3.1 If they do and SMS fails again, then the process will restart from step # 1.
Development guides are available in the "Android" section of the Community Health Toolkit Docs Site. You will find instructions of how to setup your development environment, build and test new features, how to work with "flavor" apps, release, publish... and so on.
- npm
More details of how to setup and build the app here. The following are the most common tasks:
To build locally and install to an attached android device:
make
To run unit tests and static analysis tools locally:
make test
To run end to end tests, first either connect a physical device, or start an emulated android device, and then:
make test-ui
End to end tests only run in devices with Android 4.4 - 9.0. Also it's possible that at the end of the tests when the SDK tries to uninstall the app from the device the following error is shown:
com.android.build.gradle.internal.testing.ConnectedDevice > runTests[4034G - 6.0] FAILED
com.android.builder.testing.api.DeviceException: com.android.ddmlib.InstallException: INSTALL_FAILED_VERSION_DOWNGRADE
Don't worry about that, it means the tests ran OK, but the SDK failed to remove the app for compatibility issues with your device, but this error only happens with the tests.
There is a demonstration implementation of a server included for cht-gateway to communicate with. You can add messages to this server, and query it to see the interactions that it has with cht-gateway.
To start the demo server locally:
make demo-server
To list the data stored on the server:
curl http://localhost:8000
To make the next good request to /app return an error:
curl --data '"Something failed!"' http://localhost:8000/error
To add a webapp-originating message (to be send by cht-gateway):
curl -vvv --data '{ "id": "3E105262-070C-4913-949B-E7ACA4F42B71", "to": "+447123555888", "content": "hi" }' http://localhost:8000
To simulate a request from cht-gateway:
curl http://localhost:8000/app -H "Accept: application/json" -H "Accept-Charset: utf-8" -H "Accept-Encoding: gzip" -H "Cache-Control: no-cache" -H "Content-Type: application/json" --data '{}'
To clear the data stored on the server:
curl -X DELETE http://localhost:8000
To set a username and password on the demo server:
curl --data '{"username":"alice", "password":"secret"}' http://localhost:8000/auth
It's simple to deploy the demo server to remote NodeJS hosts.
TODO walkthrough
TODO walkthrough
- Create a git tag for the version, eg:
v1.7.4. - Push the tag to the repo and GitHub Actions will build and publish the apk to GitHub.
- Announce the release on the CHT forum, under the "Product - Releases" category.
Some changes were made to the Android SMS APIs in 4.4 (Kitkat®). The significant change was this:
from android 4.4 onwards, apps cannot delete messages from the device inbox unless they are set, by the user, as the default messaging app for the device
Some reading on this can be found at:
- http://android-developers.blogspot.com.es/2013/10/getting-your-sms-apps-ready-for-kitkat.html
- https://www.addhen.org/blog/2014/02/15/android-4-4-api-changes/
Adding support for kitkat® means that there is some extra code in cht-gateway whose purpose is not obvious:
Activities HeadlessSmsSendService and ComposeSmsActivity are declared in AndroidManifest.xml, but are not implemented in the code.
The BROADCAST_WAP_PUSH permission is requested in AndroidManifest.xml, and an extra BroadcastReceiver, MmsIntentProcessor is declared. When cht-gateway is the default messaging app on a device, incoming MMS messages will be ignored. Actual WAP Push messages are probably ignored too.
To support being the default messaging app, cht-gateway listens for SMS_DELIVER as well as SMS_RECEIVED. If the default SMS app, we need to ignore SMS_RECEIVED.
Since Android 6.0 (marshmallow), permissions for sending and receiving SMS must be requested both in AndroidManifest.xml and also at runtime. Read more at https://developer.android.com/intl/ru/about/versions/marshmallow/android-6.0-changes.html#behavior-runtime-permissions
Copyright 2013-2021 Medic Mobile, Inc. [email protected]
The software is provided under AGPL-3.0. Contributions to this project are accepted under the same license.